A modern alpine ski comprises a core of synthetic material wrapped or sandwiched between various layers of fibrous synthetic material such as glass fibers, graphite, kevlar or the like, impregnated with a suitable resin. To provide good gliding characteristics, a base of plastic material which comes in direct contact with the snow is used because of its low coefficient of friction. To facilitate steering maneuvers, hard metallic edges are mounted on each side of the plastic base for biting into hard icy surfaces.
When the ski is used on rough terrain, stones or similar hard objects may contact and scratch the base. The damages must be repaired quickly because if water is allowed to enter the ski through the scratches on the base, delamination of the base may result.
A current technique for repairing the base of an alpine ski consists of filling the scratches on the base with molten plastic material and when the plastic material has hardened, the base is sanded to obtain an even surface. The sanding operation is performed with a wet belt-type sanding machine on which the operator passes the ski, the base being in contact with the sanding belt. This operation is difficult to perform because the speed at which the ski is passed on the sanding belt as well as the pressure applied on the ski must be kept constant, requiring great skill and experience.